Table 3.
Proposed regression analyses with fixed and random effects coding.
| Model | Outcome | Fixed Effects | Fixed Effects Coding | Random Effects |
|---|---|---|---|---|
| 1a: Treatment-level (Treated Language) | Item accuracy for Trained and Control Items | Session | Continuous | |
| Item Set | Contrast Coding (-1 for Control Items, 1 for Trained Items) | (Session|Participant) | ||
| Treatment Language | Contrast Coding (-1 for L2, 1 for L1) | (1|Item) | ||
| 1b: Treatment-level (Untreated Language) | Item accuracy for Translations of Trained and Control Items | Session | Continuous | |
| Item Set | Contrast Coding (-1 for Control Items, 1 for Trained Items) | (Session|Participant) | ||
| TreatmentLanguage | Contrast Coding (-1 for L2, 1 for L1) | (1|Item) | ||
| 2a: Individual-level (Treated Language) | Item accuracy for Trained Items | Session | Continuous | |
| Treatment Language | Contrast Coding (-1 for L2, 1 for L1) | (Session|Participant) | ||
| Naming Severity | Continuous (z-scored BNT) | (1|Item) | ||
| Age | Covariate, Continuous (centered) | |||
| 2b1: Individual-level (Untreated Language) | Item accuracy for Translations of Trained Items | Session | Continuous | |
| Treatment Language | Contrast Coding (-1 for L2, 1 for L1) | (Session|Participant) | ||
| Naming Severity | Continuous (z-scored BNT) | (1|Item) | ||
| Age | Covariate, Continuous (centered) | |||
| 3a: Lexical Frequency | Item accuracy for Trained Items | Session | Continuous | |
| Log Frequency | Continuous, Log-transform | (Session|Participant) | ||
| Stimulus Language | Covariate, Contrast Coding (-1 for English, 1 for Spanish) | (1|Item) | ||
| 3b: Phonological Length | Item accuracy for Trained Items | Session | Continuous | |
| Length | Continuous | (Session|Participant) | ||
| Stimulus Language | Covariate, Contrast Coding (-1 for English, 1 for Spanish) | (1|Item) | ||
| 3c: Phonological Neighborhood Density | Item accuracy for Trained Items | Session | Continuous | |
| Log Density | Continuous, Log-transform | (Session|Participant) | ||
| Stimulus Language | Covariate, Contrast Coding (-1 for English, 1 for Spanish) | (1|Item) |
Note.
1
The model structure for 2b was altered slightly given the outcomes from model 1b. Justification is provided in the Results section. Log frequency = log-transform of lexical frequency; Log density = log-transform of phonological neighborhood density.